Spark plug



Patented July 29, 1924.

Y DOVNALI.) W. WILLIS,` OIE CANTON, OHIO.

vSPAR-K PLUG.

Application 1ed October 19, 1921. Serial No. 508,892.

To all whom t may concern:

Be it known that I, DONALD 1V. VILLis, citizen of the United States, residing at Canton, in the county of Stark and State of Ohio, have invented certain new and useful Improvements in Spark Plugs, of which the following is a specification.

This invention relates to an improved spark plug and has as one of its principal objects to provide a plug which may be easily and quickly disassembled so that the plug may be readily cleaned or the electrodes cheaply renewed.

A further object of the invention is to provide a plug employing' a block carrying the insulator and electrodes of the plug and wherein said block may be removed for displacing the electrodes and said insulator as a unit.

And the invention has as a still further object to provide a plug wherein the block will serve to close the plug shell and wherein the block may be tightly clamped in position coacting with the shell.

Other and incidental objects will appear hereinafter.

In the drawing:

Figure 1 is a side elevation of my improved plug, parts being broken away and shown in section,

Figure 2 is a vertical sectional view through the plug,

Figure 3 is a sectional view on the line 8-3 of Figure 2, looking in the direction of the arrows,

Figure 4 is a perspective view showing the electrode unitof the plug, and

Figure 5 is a fragmentary section showing a slight modification of the invention.

Referring nowY more particularly to the drawing, I employ a shell 10 which is preferably squared at its upper end while the lower end portion of the shell is threaded to engage in the usual spark plug orifice of an engine cylinder. Projecting from the squared upper end of posite sides thereof are trunnions 11 and formed in the shell at Vits upper end is an annular recess or seat 12. Fitting in this seat is an appropriate gasket 13 and cooperating with said gasket is a closure block 1.4 for the shell. Extending through this block from one side thereof. to project through the lower end of the block axially of the shell is an insulator 15 embedded in Velectrode carries a the shell at op-` the block vand extending through said insulator is a center electrode 16 projecting through the shell. At its upper end, this washer 1 7 to coact with the insulator and threaded upon the electrode is a binding nut 18. Embedded at its upper end in the lower end of the block 1s a ground electrode 19 extending through the shell to the lower end of the electrode 16 to provide a spark gap between the electrodes and formed on the block at opposite sides of the upper end of the insulator 15 are vertically disposed reinforcing ribs 20. As will be observed upon reference to Figure 4, the block 14 with its insulator 15 and electrodes 16 and 19 provides a single unit which may be bodily displaced from the shell. Mounted to swing upon the trunnions 11 is yoke 21 and threaded through this yoke is a clamping screw 22 upon the lower end of which is swiveled a plate 23 to coact with the upper end of the block 14, while at its upper end said screw is provided with a hand wheel 24. Thus, as will be seen, the clamping screw may be adjusted to coact with the block 14 for coin-- pressing the block against the gasket 13 so as to provide a sealed joint between the shell and block, the ribs 2O being designed to prevent distortion of the block suoli as would cause fracture of the insulator 15. At the same time, by releasing the screw, the yoke 21 may be swung to one side, when the electrode unit of the plug may be readily detached from the shell. I accordingly provide a plug which may be easily and quickly cleaned.

In Figure 5 of the drawing, I have illustrated a kslight modification of the invention wherein the plug shell, indicated at 25, is formed at its lower end with an internal annular flange 26 through which is a central opening 27. The center electrode 0f the plug, indicated at 28, is arranged to project through this opening to provide a spark gap between the electrode and the flange, the ground electrode 19 as illustrated in connection with the preferred construction, being eliminated. Otherwise, this modified structure is identical with the preferred form of the invention.

Having thus described the invention, what is claimed as new is:

1. A spark plug including a shell, a block closing the shell at its upper end, an insulator extending through the block to project at its upper endV atV one side of the block, a main electrode extending through said insulator Within the shell, a ground electrode upon the block to cooperate With the main electrode, reinforcing ribs upon theV block at opposite sides of the projecting upper end of said insulator, and means coacting with the upper end of the block clamping the' block upon theshell.

2. A spark plug Vincluding' a shell, a block Vclosing the shell at its upper end, a

longitudinally curved insulator extending through the block to'projett throughV the side wall thereof, an electrode upon said insulator, and means coacting with the upper end of the block axially of the shell secur ing the block in position.

3. In a spark plug, the combination with a shell threaded for engagement in an engine cylinder, an insulator of brittle materia-l, and an electrode carried by the insulator, of a block closing the shell at its upper end and mounting vthe insulator, and adjustable means coacting With the upper end of the block axially oit ,the shell vclamping the blockl inposition, the block beingV #adapted to withstand compressive stress whereby to vprevent fracture of the Y inv "sulaton In testimony' Whereof'l alix my Signature.

DONALD W. WILLIS. [ns] 

